Caravan Servicing

Explore the art of caravan servicing on this page. It is recommended that a caravan is serviced by a dealer at the start of every new touring season. To satisfy the warranty on new caravans, servicing is compulsory until the caravan is out of warranty. As you may have a classic or vintage caravan, surely because it is long out of warranty, it doesn't need servicing? Think again.
A routine service checks every aspect of the caravan; from damp checks to brake adjustments and corner steady lubricating to gas pressure testing. Think of it as an MOT for caravans. Caravan dealers typically quote anywhere from £90 - £200 for a service (fixed price per dealer, dealer dependant) and this covers parts and labour. A caravan dealer workshop service is approved by both the National Caravan Council for the UK and the respective caravan manufacturer. A service is a standard procedure at all dealers and they all follow the same checklist set by both the National Caravan Council and the respective caravan manufacturer. However, you can still service parts of your caravan yourself. You do not need fancy electronic gadgets and expensive tools; just some know how and a decent tool set. The good news is that modern caravans are a lot more technically advanced than older caravans - consequently, more basic and simpler servicing is required for older models - so much so that a competent DIY'er can easily carry out their own caravan servicing.
Here is a comprehensive 10 part servicing procedure for your caravan. I have based it on my own 1988 ABI Award Dawnstar caravan, expect some slight variation with your caravan. You can click on the images to enlarge them.


1. The Chassis                                    COST: few £'s for lubricant   DIFFICULTY: 1, Easy
The chassis is the most important part of a caravan. It carries the entire weight of the caravan and allows it to be transported. It is therefore essential to keep the chassis - if nothing else - in top working order. The chassis will need regular attention, especially if it is an older chassis. Al-Ko introduced their revolutionary chassis to the UK in 1985 and since has slowly become the industry standard. It is poignant because it is galvanised. This means that the chassis has a protective layer to prevent it from rusting or corroding. All other older chassis types (B&B, Peak Trailers, Rubery Owen as well as manufacturers own respective chassis' types) require re-painting periodically to stop them rusting. Providing that they are painted properly, they should be ok for around three years before they should be painted again. 
Despite the chassis type, regular lubrication is paramount. I would recommend that you lubricate immediate parts (corner steadies, jockey wheel) as and when felt needed: ie, when you feel they aren't moving as freely as they should. All other parts (brake linkages, handbrake lever) should be lubricated periodically as necessity - usually at the start of your touring season. Apply lubricant to these areas in suitable amounts there should be still some slight resistance but parts should move freely. All caravans have hitch heads (known as the tow hitch or coupling) which need to be lubricated in some way. All tow hitches require a little lubricant on moving parts such as the handle when needed - BUT NEVER INSIDE THE TOW HITCH WHERE IT CONTACTS THE TOW BALL. At the tow hitch end, push hard on the tow hitch (with the handbrake on) to check that the hitch damper is working. The hitch should retract, and if it doesn't, then the hitch damper needs greasing. *Note that imported caravans may not have this feature. Some will have a solid hitch welded to the front of the A-Frame (Such as Airstream, Scotty, Fleetwood etc) If they have a total weight of less than 750kgs then this is fine, but if they weigh over 750kgs fully laden then to comply with UK laws and regulations a conversion must be performed to incorporate the automatic braking feature. Consult a caravan importer for more details.* Hitches equipped with the auto reverse feature require greasing via the designated grease nipples. These points will be clear on the A-Frame if the caravan has them, and can be spotted on the enclosure immediately behind the tow hitch. If your caravan has an A-Frame fairing (essentially a plastic moulded cover to cover the metalwork), this needs to be removed to access these. Simply locate the screws to take it off. If you don't have auto reverse (when you move the caravan backwards, the brakes apply instead of disengaging) you still have to grease the hitch damper - there should also be some grease nipples behind the hitch. Other than that there is nothing to lubricate other than perhaps the small metal piece that holds the hitch in the extended position to allow reversing - NEVER LEAVE THIS PIECE IN PLACE WHILST TRAVELLING FORWARDS AS IT DISENGAGES THE BRAKES.
Below is a diagram of a typical chassis used on older caravans (B&B design) from the 1950's - 1980 when it was replaced with the Al-Ko chassis design.
Below is a diagram of a basic Al-ko chassis, which is similar to most caravan chassis' used in the 1980's - the present day: 
Suitable lubricants include grease (grease in spray form works well too) and suitable car lubricants. It is advisable not to use light lubricants and oils (such as WD40) as these are short term lubricants, not designed for long term lubrication. 
It is also worth checking the chassis mounting points to ensure correct tightness. These points are where the chassis is mounted to the caravan floor, there are recommended torque settings, but these vary greatly, so it is best just to ensure that the bolts are tight. 
Finally, check the condition of the breakaway cable which is the small cable under the hitch. If it is frayed or damaged, replace immediately. Replacements are available from caravan dealers for around £5. Give it a good pull and the handbrake should  lift and apply slightly depending on how hard you pull it. Some older caravans and imported ones will feature chains instead of a breakaway cable. These are fitted if the caravan does not have its own brakes. Check that the chains are in good condition and remember when coupling up the caravan to the car to cross the chains over instead of running them parallel. 

2. Brakes & Wheels                                       COST: £5 - £10   DIFFICULTY: 2, Moderate    
All caravans have drum brakes. All caravans are designed to apply their brakes when the towcar brakes during towing - that is unless the caravan is imported and features a solid state tow hitch. The hitch is compressed (the small tube at the back of the tow hitch compresses - you will see a black rubber concertina like device - this is called a hitch gaiter)  and this applies the brakes slightly to take the pressure off the car's brakes. Thus, it is essential that the brakes are adjusted properly. Drum brakes need re-adjusting periodically along with the handbrake. Every handbrake should apply on the third 'click' of the ratchet. They won't be applied fully, but should be enough to hold the caravan on a fairly level surface. If the handbrake doesn't apply until the fourth, fifth or even sixth ratchet 'click' then the brake cable needs adjusting. In addition to the lubricant of the brake lever (see section 1 of this page), the brake cable can be adjusted by tightening up the brake linkage. This can be found near the axle on most caravans and has a small screw based shaft to adjust the tension on the cable. Worn out or over-stretched cables should be replaced. 
Secondly, the brake drums should be adjusted. Some brake drums will have an adjustment feature at the back. To do this, jack up the caravan and ideally take the wheel off [see jacking procedure on the Safety - please read page]. With the handbrake in the OFF position, rotate the wheel in the forward direction (NOT IN REVERSE AS THE BRAKES WILL APPLY THEMSELVES). If this is hard to do then the brakes need adjusting. On models with an adjustment feature (See diagram below), use a flat blade screwdriver to adjust the starwheel in the direction of the arrow until the brake drum moves freely. Pull on the handbrake lever a few times to centralise the cable and test the tension on the Bowden cable (brake cable). With the handbrake off, pull on the cable and it should move between 5-8mm. Any more or less then the brakes need re adjusting. Wrongly adjusting the brakes will reduce their effectiveness. 

Older caravans do not have this adjusting feature, but may have something similar, check first. If not, they may need the brake drum dismantling to access adjusting levers. These are spring loaded and will adjust with a screwdriver.
On a professional service, wheel nuts are replaced. It is recommended that you do the same. They cost around £5 and up to £12 for marine grade ones. They are available from car shops such as Halfords and websites such as eBay. You should also tighten up the wheel nuts to the recommended torque setting for your particular caravan. The torque settings are typically 120nm for steel wheels and 85nm for alloy wheels. They should be tightened to the relevant settings before each journey. Bear in mind they may vary for older models (1920's-1950's), but the figures quoted above apply to most caravans. Wheel nuts should be tightened in sequence: North, South, East, West (top, bottom, right, left) to ensure that the correct tightness is attained.
Most importantly, check the condition of the tyres. Caravans stand for long periods and tyres deteriorate much quicker than those on cars. Storing your caravan on grass will damage them over time - the constant wetting of the tyres with morning dew and drying out will cause the rubber to break down - which could lead to a blowout on the road. If you have to store your caravan on grass, then placing thin pieces of wood under the tyres is a cheap preventative measure to stop this from happening. Also, caravan tyres are very prone to flat spots. Check the sidewalls for signs of deterioration. ***NOTE: Check BOTH sides of the tyre, not just the visible side. You may have to take the wheel off to do this*** Caravan tyres should be replaced at least every six years, if not more frequently. While servicing, check tyre pressures and inflate as necessary.

3. 12N and 12S sockets                                               COST: free   DIFFICULTY: 1, Easy
This check is quite simple. Connect the caravan 12N socket (Black socket) to your car socket and test that the road lights are working. You can then test the 12S socket (Grey socket) but again attaching it to your car socket and running a 12v appliance. If your caravan doesn't have a 12v system, then it won't have a grey 12S socket. Caravans that don't have a 12S socket yet still have a 12v system will have a 12v system allocation on the black socket which is pin 2. This is only so that the car's battery can be used to power the caravan's own 12v system. Should you find any issues, be sure to clean the socket pins, as these often get dirty and stop working if dirt is allowed to build up. If this doesn't solve the issues, you can open up the sockets and check that all of the wires are connected properly, see diagram below. Terminals are numbered 1-7, clockwise with 1 being the top pin and 7 being the middle pin. In 1999 the pin allocation on the 12S socket changed, most vintage caravans will have the pin allocation as per the diagram below, but your caravan may have been changed after 1999, but this is unlikely. It is worth cleaning the terminals of the sockets using pipe cleaners and light sandpaper. This is optional, but will help reduce corrosion. A little light oil such as WD40 will act as a good cleaner for the terminal contacts.

4. Damp Check                                       COST: around £25 for meter   DIFFICULTY: 1, Easy
Damp checking is not compulsory on your own service, but may provide helpful for preventing damp damage spreading. If water ingress is spotted early enough, it can be repaired without having to replace any wallboarding. Damp areas can be obvious if they are in their later stages but in the early stages of damp when it is easily treatable, it can be harder to detect. For this reason I can recommend purchasing a damp meter from online websites such as eBay and caravan dealers for around £25. These meters will give you a reading and visual indication of damp levels. You should test the areas shown below:
Of course you don't always need a damp meter, signs of damp include: mould, sponginess, air bubbles (under wallpaper) wetness, discolouration to wallboard, peeling wallpaper, warping, swelling and brittleness. There are many kinds of damp too, all treatable in various ways. Damp will always be found in the areas shown in the diagram above.

5. Gas System                            COST: varies for replacement parts   DIFFICULTY: 2, Moderate
All caravans no matter what their age will have a gas system. The trouble is that UK safety standards are altered frequently so you have to ensure that your classic caravan conforms to the current safety standards that are a legal requirement. There are only two types of LPG (Liquid Petroleum Gas) used in caravans: Butane (blue coloured bottle) and Propane (orange/red coloured bottle). It is up to you which type you use, there are pros and cons for both, but basically, Butane is better suited to summer caravanning and Propane is better suited to winter caravanning. But if you have one or the other, don't feel as if you have to change them during different touring seasons as the differences are only minor. Each type requires it's own type of gas regulator which should be the same colour as the gas bottle.
Gas Regulators:
These are the devices that fit on the gas bottle and are connected to a pipe that takes the gas to the appliances in the caravan. It is vital that you have the correct regulator.
A gas bottle mounted regulator with rubber pipe attached (middle left) 

There are two different regulators for the two different gas types (Butane and Propane). They both supply the gas at around 30mbar. Some older regulators are a plain silver colour, it is advisable to change these to the appropriate colour for the gas used (blue or red regulators) for safety's sake. These regulators are available from camping and caravanning shops and can cost between £5 and £15. As of 2004, gas bottle mounted regulators were no longer fitted to new caravans and bulkhead mounted regulators fitted instead. These new regulators can be serviced by caravan dealers unlike bottle mounted ones and they reduce the risk of gas deposit build ups. However, if used properly, bottle mounted regulators are perfectly safe. When servicing, check that the regulator is in good condition and if found to be defective or old, then replace.
Propane gas bottle with bottle mounted Propane regulator and high pressure pipe

After the regulator, the gas is supplied via a metre or so length of rubber pipe to a solid metal mounting point, usually located at floor level on the exterior (or front locker) of the caravan. This rubber pipe MUST be replaced every four years and replaced more frequently should you find it to be cracked or worn. Rubber gas piping is available from all caravan dealers for around £1.50 per metre. Modern piping is supplied with a date stamped on it, so should the existing pipe have no date on it or be more than four years old, replace it. You have two choices, high pressure piping or low pressure piping. It doesn't necessarily matter which, but I would suggest high pressure pipe.
New specification gas pipe showing date of manufacture

To replace the pipe,  TURN OFF THE GAS BOTTLE FIRST and disconnect the regulator using a regulator spanner which are available from camping and caravan shops for less than £5. These are specially suited to gas bottle regulators and are the only way to disconnect the gas bottle from the regulator. Loosen the jubilee clip with a flat blade screwdriver and give the pipe a little encouragement to come off. Do the same at the end that the pipe is connected to the caravan's metal pipework. Then, slot in the new pipe onto the points which the old pipe was removed. This may be difficult at first so you can hold the pipe in boiling water to let it expand, thus making it easier to slide on. Tighten the jubilee clips back on. You can then reattach the regulator to the gas bottle and ensuring that the regulator and pipework are tightened up, can test the gas system out.
Gas Appliances:
This is an opportunity to test the system out, especially for holes, leaks and damage. On a caravan dealer service, the workshop will pressure test the system to show any leaks or holes. If you do not have the facilities to do this, but don't worry; you can still carry out this check. Simply connect your gas bottle and light one burner on the stove inside the caravan. The flame should be a strong blue colour, any orange/yellow tips to the flame are a result of oxygen in the system, this means that there is air in the system and pipes may need replacing. It is acceptable for some light orange/yellow tips, but if the majority of the flame is orange/yellow, then there is a problem. Blockages will also be indicated by gaps in the flame. As the flame comes out of the holes in the burner, if some are missing or the flame is very low in it's full setting then there may be a blockage in the system. Should you find any problems, don't hesitate to contact either a caravan dealer or a gas technician for further advice.
You should also take the opportunity to test other gas appliances; check that all of the burners on the stove light properly, check the oven and grill (if fitted) light properly, check that the fridge (if fitted) works on gas - check it lights on gas and keeps the fridge cool (it may take a few minutes to get to temperature), check the gas fire works (if fitted) and finally check the gas water heating system (if fitted) to ensure that it works. Don't forget to check gas lights (if fitted) and replace broken mantles. Be sure to give the gas lights a good clean.When checking gas appliances, make sure that the caravan is well ventilated and if any appliance looks faulty, seek the help of a caravan dealer or gas technician.

6. 12v Electric System                  COST: varies for replacement parts   DIFFICULTY: 2, Moderate
Some caravans have a 12v electric system run from a leisure battery. Caravans started to have electric lights as early on as the 1960's and 12v systems were becoming standard as of the mid 1970's. Some older caravans may have had a retro-fitted 12v system installed by a previous owner. All systems should be checked periodically. A 12v system can power a multitude of things including lights, water taps, 12v outlets (for shavers, vacuum cleaners etc) and radios. If you have any 12v appliances, you should check that they work properly. Also take the time to check the condition of the leisure battery. Test the battery for voltage and amperage using a multimeter and then remove it from the caravan and place it on a battery charger (you can pick one up from eBay for less than £10 and pay a bit more for a decent one) until it reads 13/14 volts. Your caravan charger (if you have one fitted) may already have charged the battery to a suitable level. Always switch off all 12v appliances inside the caravan before disconnecting the battery to prevent fusing. Check the condition of the battery terminals and sand them slightly if they are corroded. Also inspect cables for any signs of damage and if the protective coating is damaged, either replace the cable or apply electrical insulation tape for temporary repairs and repairs to small amounts of damaged. Electrical insulation tape should not be used as a long term solution.

7. 230v Electric System (If Fitted)                           COST: free   DIFFICULTY: 2, Moderate
Should your caravan have a 230v system, this needs checking mainly to ensure that it works. Connect the mains lead to a power outlet and check that all appliances work as they should. Secondly, inspect the mains cable for damage. Here is a wiring diagram for the mains lead connector:
If the cable is relatively new, it should not require the wiring checking. Any damaged wires should be replaced immediately. Check that the mains charger is charging the battery properly. You can test the charge output using a multimeter (should be putting out around 14 volts) or use the battery to power appliances for a few hours to drain it slightly and see if the battery is charged up again when the charger is switched on. Also ensure that circuit breakers are up to standard and that they are effective - most RCD circuit breakers should have a test function: press it to ensure that the switch trips off. You should also check earthing points for any signs of corrosion.

8. Water System                                                  COST: around £3   DIFFICULTY: 1, Easy
Fill a water container with water and check that the water system delivers water to the taps. Owners of caravans with an electric water system have an external pump (pictured) but caravans with foot pumps have a simple pipe. On a service, this pipe should ideally be replaced unless you have a 12v system water pump as per the image below - in which case the water filters should be changed. Consult your caravan dealer for more information.
It is advisable to clean out the water system on a service. Water purification power can be purchased for around £3 from caravan dealers and online. Each product is different, but essentially you put the designated amount of powder into the water container and run the taps to flush it through the system. Then you keep flushing fresh water through the system until the water comes through clear again. Follow the instructions on the label, and to be safe you can flush the system through one more time than the designated amount on the packet. Any water system can be cleaned out.
12v operated systems may require new filters. Each system is different, but usually where the water inlet pipe is connected to the exterior of the caravan, there is a small unscrew-able lid which reveals a small removable filter unit. Alternatively, it may be under the bunk where the water system is located. These filter units can be bought from caravan dealers and the internet for around £4. A filter cleans out impurities in the water supply to provide fresh water to the taps.

9. Fitted Appliances                                                   COST: free   DIFFICULTY: 1, Easy
Some caravans will have different appliances fitted. These should be tested out to ensure that they work and any maintenance such as lubrication should be carried out. A popular addition to vintage caravans is the fitting of a cassette toilet. This is a built in toilet with a tank which can be removed via the exterior of the caravan. This tank should be cleaned out using appropriate cleaning solutions and the cassette mechanism should be lubricated. You can also keep the seals in top condition using a spray by caravan toilet manufacturer Thetford. A 250ml spray can is around £7 from caravan dealers and will last years.

10. Finishing Off                                                          COST: free   DIFFICULTY: 1, Easy
Finally, your caravan is ready to go. Treat it to a clean and a tidy up before embarking on your next journey. Remember to double check the tightness of the wheel nuts (see section 2) and check that the road lights work and you're ready for your next holiday!

I hope this article was helpful, please contact me with any comments and suggestions on how to improve it. Also as usual, feel free to ask any questions.